Missile transfer dolly



Allg 15, 1961 E. s. cULvx-:R

MIssILE TRANSFER DOLLY '7 Sheets-Sheet l Filed March 20, 1959 INVENTORATTORNEYS Aug. 15, 1961 E. s. CULVER 2,996,310

MISSILE TRANSFER DOLLY Filed MaICh 20, 1959 7 Sheets-Shea?l 2 mvENToREugene S. Culver BY y o @my ATTORNEYS Aug. 15, 1961 E. s. cULvER y2,996,310

MIssILE: TRANSFER DoLLY '7 Sheets-Sheet 3 Filed March 20, 1959 aJvvuJ-zATTORNEYS Eugene S. Culver '7 Sheets-Sheet 4 Filed March 20, 1959INVENTOR Eugene 5. Culver ATTORNEYS Aug- 15, 1961 E. s. CULVER MISSILETRANSFER DOLLY 7 Sheets-Sheet 5 Filed March 20, 1959 2 a @Em INVENTOREugene 5. Culver BY i@ W MM ATTORNEYS 7 Sheets-Sheet 6 INV EN TOR Eugene5. Culver CQ f@ ATTORNEY 8 Aug. 15, 1961 E. s. CULVER MIssILE TRANSFERDoLLY Filed March 2o, 1959 Aug 15, 1961 E. s. cULvER 2,996,310

MssILE TRANSFER DoLLY Filed March 2o, 1959 7 sheets-sheet fr INV ENTOREugene S. Culver Q f am 1, BY W ATTORNEYS United Sates 2,996,310 MISSILETRANSFER DOLLY 'Eugene S. Culver, Arlington, Va., assigner to the UnitedStates of America as represented by the Secretary of the Na Vy FiledMar. 20, 1959, Ser. No. 800,901

8 Claims. (Cl. 2S0-124) This invention relates generally to materialhandling apparatus which is especially suited for transporting ordnancedevices, such as guided missile components, from ship to ship at sea, orfrom dockside to ship. More specifically, the invention pertains to animproved transfer dolly which constitutes a significant part of aneicient, integrated system for handling the components of a guidedmissile from the time of issue thereof from a shore-based depot todelivery aboard a missile firing ship, including introduction of suchmissile components into the ships strike-down system.

Another object of the invention resides in the provision of a transferdolly which will function to protect missile components during thestages of handling where shock loading may 4become excessive, and whichwill at the same time permit extreme mobility of such components onshipboard, said dolly employing means for isolating such components fromshock from any direction in the horizontal plane, and means forproviding shock protection in the vertical plane, the last-mentionedmeans being constituted by a unique constant deceleration torsion barsuspension system.

Still another object of the invention is to provide a missile componenttransfer vehicle which incorporates a novel dead man brake mechanismthat will insure immediate arrestrnent of the vehicle after it has beendeposited on the deck of a ship, but which may be quickly released,either by hand or by the action of a hoisting sling, for permittingmovement of the vehicle to a desired location on the deck.

A further object of the invention is to provide a missile componenttransfer dolly that is constructed of light weight, high strength steel,heat treated to attain very high working stresses, for insuring maximumprotection for missile components thereon.

Other objects and many of the attendant advantages of this inventionwill be readily appreciated as the same becomes better understood byreference to the following detailed description when considered inconnection with the accompanying drawings wherein:

FIG. l is a perspective view of the improved transfer dolly with acomponent cradle mounted thereon;

FIG. 2 is an end view of the transfer dolly;

FIG. 3 is a side elevation of the dolly;

FIG. 4 is an enlarged detail side elevation showing the positions of thesupporting legs, the torsion bar levers, and the shock absorbermechanism under impact conditions;

FIG. 5 is a detail view of one of the torsion bars employed, togetherwith its associated levers;

FIG. 6 is a top plan view of one end of the transfer dolly;

FIG. 7 is an enlarged detail perspective view showing particularly thebrake cylinder mechanism, portions of the torsion bar and shock absorbermechanisms, and one of the cradle latches;

FIG. 8 is a detail perspective view showing the torsion bars and themountings therefor;

FIG. 9 is a diagrammatic representation of the basic suspension system;

FIG. 10 is a detail perspective view showing a modified cradle latcharrangement;

"ice

FIG. 11 is an enlarged front elevation of one of the caster wheelstructures; and

FIG. 12 is a side elevation, partly in section, of the caster wheelstructure shown in FIG. 11, particularly illustrating the brakemechanism.

Briefly, the transfer dolly constituting the present invention is adolly of high strength tubular frame construction including a nearlyuniform (within 1 percent) deceleration suspension system to provide themaximum in energy absorption in a minimum area of deection. The purposeof such a design is to provide the maximum protection vfor a load fromshock, while also permitting easy movement of the dolly after depositthereof on the deck of a ship, and extreme ease and speed in removingthe load from the dolly. The weight of the dolly has been reduced to theminimum to assure ease in handling by manpower on a rolling deck andduring ship-to-ship or ship-to-shore transfer operations.

The suspension system that provides protection from the most likelyoverload, Le., an uncontrolled free-fall drop to the deck of a ship,comprises basically three lever linkage arrangements at each end of thedolly that act on pairs of torsion bars controlled by hydraulic shockabsorbers. The legs, with full castering wheels thereon, areindividually sprung, for maximum flexibility. The castering Wheels areprovided with locks to prevent accidental directional changes. Theoperation of the linkage system is such that the Hookes law action ofthe torsion bars is multiplied to produce nearly uniform deceleration ifthe dolly is accidentally dropped. The operation of the linkage systemis also such that it will absorb twice as much energy as previouslyknown suspension systems while transmitting the same or less shock tothe suspended load.

The cradle employed with the transfer dolly, for carrying a missilecomponent or other load, is formed of light gauge sheet metal properlyreinforced. The cradle is padded with sponge rubber to prevent chang amissile component or other load therein. Quick operating latches areemployed to permit rapid removal of the cradle from the dolly. Thecradle is so designed that a number of them may be stacked, by the useof suitable cranes or trucks, if desired.

Referring to -the drawings in more detail, the general arrangement ofthe improved transfer dolly is shown in FIGS. 1, 3, and 6. The dollycomprises a frame 10 which includes side rails 11 and 12 and generallysemielliptical end rails 13 and 14, the end rails being connected to theside rails by suitable couplings, one of which is indicated at 15. Theframe is substantially rectangular in shape and is formed of lightWeight, high strength steel tubing, heat treated to attain extremelyhigh working stresses, say of the order of approximately 120,000 p.s..Mounted on the side rails near their opposite ends are verticallyextending generally inverted U-shape guard rails 16. Extendingtransversely of the frame near the opposite ends of -the side rails aretubular supports 17, best seen in FIGS. 6 and 7, and carried on saidsupports are support plates 17a. The supports 17 carry cradle mounts 18which are mounted on preferably rubber shear blocks 19, said mountshaving flat upper surfaces and carrying latches 20 at their oppositeends. 'Ihe cradle mounts 18 and latches 20 will be described in moredetail hereinafter. The cradle mounts and latches cooperate withmounting saddles 21 on a cradle 22 (FIG. l) which is designed to carry amissile component or other load on the dolly.

The torsion bars which constitute a part of the deceleration system forthe transfer dolly fare mounted in pairs and extend transversely of theframe near its opposite ends. Since the pairs of torsion bars areidentical 3 in constructionV and application, a description of one pairwill suflice for both. As best seen in FIGS. 5, 6, 7 and 8, the torsionbars of one pair are indicated at 23 and 24 and are of cylindricalcross-section. Referring particularly to FIG. 6, the torsion bar 23 hasone end mounted for limited rotation in plates 25 and 26 which aresecuredl to and extend above the side rail 11, and the other end rigidlymounted on a 'plate 27 which is secured to .and extends above the siderail 12. Secured to the bar 23 near the rail 11 and extending above theframe is a .bar lever 28. The torsion bear 24, which lies in parallelspaced relation to the bar 23, has one end rigidly secured to the plate25 and the other end mounted for limited rotation in the plate 27 and ina companion plate 27a. A 'bar lever 29, identical to the bar lever 28,is rigidly secured to and extends above the torsion bar 24 near theVside rail of the frame 10. Asbest seen in FIGS. and 7, end plates 30and coupling plates 3i provide suitable means for rigidly connecting thetorsion bars to the frame and the levers to the torsion bars.

Four leg assemblies are used for supporting the transfer dolly. Ihey areindependently mounted on the frame and constitute a part of thedeceleration system, cooperating with the tor-sion bars and theirassociated bar levers. One of the leg assemblies is mounted on the frame1G near each corner thereof. The leg assemblies are identical so that adescription of one will sutiice for all four.

The best showing of one of the -leg assemblies will be found in FIG. 4of the drawings, a typical leg assembly being indicated generally `at32. It comprises a leg element 33, a lever element 34, and a brace 35.The leg element and brace are of tubular hardened steel, said legelement extending below the frame and terminating at its lower end in acaster mount 36. At its upper end the leg element is mounted on theframe by a trunnion 37 (FIG. l). The lever element 34 is constituted byya pair of parallel spaced plates 3S and 39 which are of triangularshape. As mounted the plates resemble, in side elevation, a generallyequilateral triangle with the base lying in a plane nearly normal to theplane of the side rail l2 and the apex extending toward the nearest endof the-frame, when the deceleration system is unstressed. Thelowermostcorner of the lever element straddles the upper end of the legelement 33. on the trunnion 37, and the upper end portion of the brace35 is secured to said lever element near the apex thereof, thus addingrigidity to the lever element. The lower end portion of the brace issecured to the'leg element 33 near the caster mount 36.

Positioned between the apex of the lever element 34 and Vthe frame is insingle lacting shockabsorber 40 which includes a cylinder 41 that hasone end connected to a trunnion 42 journaled by the legs of a yoke 43secured to the side rail 12 adjacent the vertical portion of the guardrail 16 nearest the end rail 13. The shock absorber carries a pistonincluding a piston rod 44 which is pivotally connected to the apex ofsaid lever element 34, a conventional sump 45 being mounted on the uppersurface of the cylinder 41. A cable 46 connects the upper end of thelever 28 with the upper end of the lever element 34.

As will be explained in more detail hereinafter, the pairs of torsionbars 23 and 24 are partially Vpreloaded during installation, With theresult that the lever elements of the leg assemblies are normally rockedin the direction of the ends o fthe frame by the action of the levers 28and the cables 46. To prevent movement of the leg assemblies beyond theunloade positions shown in FIG. 3 by the `action of said prestressedtorsion bars, cables 47 are employed and are connected from points nearthe upper ends of the lever elements 34 tothe side rail 12 near theinnermost vertical members of the guard rails 16.

The caster and brake. structure lare shown in FIGS. 11 `and l2 and willnow be described. Each of the four casters employed` includes, inaddition to a caster mount 36, a yoke 48 having a hollow stem 49. Thestem 49 is mounted for full 360 degree rotation in the mount 36 bybearings 50 and 51, and is limited against vertical displacement by anut 52 which engages a top plate 53. To prevent fouling by salt water inthe event of accidental immersion of the dolly, suitable O rings sealthe mount 36 at its upper and lower ends. The yoke 48 rotatably mounts acaster wheel 54 which has sets of brake studs 56, the studs of each ofsaid sets being arranged in an annular series and projecting from theside faces of the wheel. The brake studs 56 are selectively engageableby notched shoes 57 that are mounted between the legs of the yoke and atopposite sides of the wheel by a cross rod 5S, and are connected t0 aplunger 59 in the hollew stem 49 by links 60 and 61. A spring 62 in thestem normally urges the plunger downwardly for engaging the shoes withstuds 56 at each side of the caster wheel 54.

A hydraulic brake cylinder 63 is pivotally mounted on the brace 35 ofthe leg assembly by a U-shape strap 64, with the piston 65 of saidcylinder rigidly secured to said brace by a bracket 66. The strap 64 isconnected to the upper end of the plunger 59 by a link 67 and a nut 68.It will be seen that hydraulic lluid introduced to the cylinder 63 willmove said cylinder away from the fixed piston 65 for raising the link 67and the plunger 59, when the brake shoes will be disengaged from thestuds 56. To prevent directional changes in wheel attitude of the casterwheel 54, a spring Pressed lock plunger 69 is normally engaged in asuitable opening or notch in the forward end of the yoke 48. A handle 70on the plunger 69 may be raised for freeing said plunger from the holeor notch, when the caster may be rotated as desired. The casters may belocked at degree angles to each other for providing a parking brake forthe dolly.

The brake mechanism described above forms a part of a hydraulic brakesystem for the transfer dolly. More specifically, in addition to thecasters and their associated brake structures, mounted on the four legassemblies, there is provided a master cylinder having main andauxiliary brake pistons. A hydraulic line H, as best shown in FIGS. 1and 7, connects the master cylinder with frame 10, as at 10', the framebeing in iluid communication with the cylinder 63 of each caster in anyconventional manner. The hydraulic brake system is best seen in FIGS. 4and 7 of the drawings. The master cylinder is shown `at 71 and the mainand auxiliary pistons at 72 and 73, respectively. The master cylinder 71is mounted on an extension of the plate 25 near one corner of the framewith the pistons projecting toward the nearest upright section of theyadjacent guard rail 16. The main piston 72 is operated manually by alever 74, mounted on `and extending along the horizontal section of theguard rail 16, and a connecting rod 75. The auxiliary piston is operatedby a cable sling 76 having a branch 77 connected to said auxiliarypiston by a pivoted link 78.

Briefly, the hydraulic brake system operates as follows. When thetransfer dolly is being moved from, say an ammunition ship to a cruiser,rand is being handled according to the well-known Burton (high-line)method, the caster brakes are maintained in the ot^positions, that is,with the notched shoes 57 out of engagement with the studs 56 of thecaster wheels, due to operation of vthe auxiliary piston 73 by thebranch 77 of the sling 76. When the dolly contacts the deck of thecruiser, the sling will slacken and pressure on the piston Will berelieved. The shoes 57 Will then engage the studs 56 for locking thecaster wheels and preventing free rolling of the dolly onthe deck.Release of the brakes, for permitting desired movement of the dolly, maybe accomplished by depressing the lever 74 for operating the main piston72. The caster brakes will be reapplied immediately upon release of thelever 74. The operation of the auxiliary piston by the sling 76,however, involves a two second lag, to permit the leg assemblies todeflect normally upon impact with the deck, if the dolly is dropped,without skidding the caster wheels.

The mechanism for mounting and retaining the cradle 22 on the transferdolly will now be described. As shown diagrammatically in FIG. 2, thedolly is so designed that it may accommodate a relatively narrow cradleor one of `greater width.

The cradle mounts 18 extend along the tubular supports 17 thereabove, onthe shear blocks 19 and the plates 17a. The mounts 18 are of identicalconstruction so that a description of one will suce'for both of them.Each mount 18 is substantially inverted U-shape in cross-section and hasa resilient pad l80 on its upper surface. At the opopsite ends of themount 18 are pairs of aligned notched slots 81, and mounted in each saidpair of slots for swinging movement are links 82 which are pivotallyconnected at their upper ends, by bolts 82a, to one of the latches 20,said latches being of generally oblong, rectangular shape. The latches20, as best seen in FIG. 7, are each formed with a recess 83, the wallsof which are apertured near their free ends to receive the end portions84 of a hairpin shape spring latch element 85.

By referring to FIGS. 1 and 2 it will be seen that the latches 20 ateach end of the mount 18 may be swung to engage between spaced walls ofthe mounting saddle 21 of the cradle 22, the tines of the spring latchelements being manually compressed to permit entry of the end portions84 between said walls. Upon release of pressure upon the tines, the endportions 84 will engage in suitable openings 86 in said mounting saddlewalls, and the bolts 82a will engage in notches 85a in said walls. Bymoving the links 82 in the notched slots 81 the latches 20 may bepositioned for retaining on the dolly either a relatively wide cradle,such as is designated A in FIG. 2, or a relatively narrow one, shown atB.

To retain the mounts 18 against displacement from the dolly, chain linkcouplings 87 (FIG. 2) provide nonrigid connections between thecentralportions of said mounts and the transverse supports 17.

Referring now to FIG. l0, wherein a modified latch structure is shown,'a portion of a cradle similar to the cradle 22 is shown at 88. Thecradle 88 is provided with a mounting saddle 89 having spaced walls 90formed with aligned notches 91 and openings 92, the latter similar tothe openings 86. The cradle 88 is positioned on a cradle mount 93 whichis supported on shear blocks, one of which is shown at 94; a transversesupport 95 similar to the support 17; and a support plate 96 similar tothe support plate 17a. The cradle mount 93 is generally similar to thecradle mount 18 except that, in lieu of the slots 81 a loop is providedat each end, one of said loops being shown at 97. Latches 98 are mountedfor swinging movement in the loops 97 on each end of the mount 93 byspaced links 99, a pin 100, and bolts 101. The latches 98 are similar tothe latches 20 and each includes a latch element 102 having end portions103.

iIn use, when it is desired to secure a cradle on the dolly, employingthe modified latch structure, the latches 98 are swung upwardly toengage between the walls of the mounting saddle 89, the latch elements102 being compressed manually for permitting entry of the end portions103. When manual pressure is relaxed, the end portions 103 will beengaged in the openings 92 and the bolts 101 seated in the notches 91,in latching position.

As stated hereinabove, the shear mounts 19 provide protection byisolating the dolly load from shock in all directions in the horizontalplane. Shock protection for such load in the vertical plane is providedby the substantially constant deceleration torsion bar suspensionsystem, the operation of which will now be described in more detail.

The basic torsion bar suspension system is shown in FIG. 9, and theaction is as indicated in the following formula:

The load at P in the vertical direction results in an increasing torqueat Pivot T1, this increase in torque taking place at a rate equal to thelinear Hookes law rate of the torsion bar, which is acting at T1, by thefollowing:

This system produces pure uniform deceleration only if link L isinfinitely long, where the interaction of R1 and R2 would be zone. Inthe actual system described and illustrated the link L is less than 36inches long, which introduces a slight modification of the sinefunction, resulting in a slight (less than 1%) non-linearity in thesystem. Therefore, it has been stated that the system producessubstantially uniform deceleration.

At installation, `as previously stated, the torsion bars 23 and 24 arepreloaded approximately 35 degrees and `are restrained in such positionsby the cables 47. This initial wind-up establishes the load at which theleg assemblies begin to deflect. Por a tested prototype the load was setat four gravity units, i.e., four times the weight of the load on thedolly. Thus, in order to activate the suspension system, the energyresulting from dropping the loaded dolly must be sufcient to exceed theenergy prestored in the torsion bars. That is, since the torque appliedto the torsion bar is proportional to the angular deection thereof, itis apparent that the load must increase in order to attain greaterdeflections. To combat this undesirable condition the load istransmitted from a wheel of the dolly to a torsion bar through a seriesof multiplying cosine linkages such that when the initial preload offour gravity units has been reached, the leg assemblies begin to deflectand the loading remains constant for the full deiiection of the system.If a simple Hookes law spring suspension system were used and otherconditions were equal, the shock transmitted to the dolly load would betwice that produced by the 'system above described. The shock absorbers40 effectively control the rebound stroke of the suspension system, in aconventional manner,

The cradles 22 are so designed that they may be easily handled by asuitable hoist or by a fork lift truck, and may be stacked while instorage, if desired.

Obviously many modifications and variations of the present invention arepossible in the light of the above teachings. It is therefore to beunderstood that within the scope of the appended claims the inventionmay be practiced otherwise than as specifically described.

What is claimed is:

l. In a transfer dolly, a frame, a leg assembly pivotally mounted on theframe and having Ia lever element and a leg element, said leg assemblybeing deflectableupon impact of the dolly with a surface, a spring onthe frame and having one end secured to said frame and the other endmounted for limited movement, a bar lever on the spring, first ycablemeans connecting the bar lever to` the lever element, said spring beingso preloaded that the energy required to deflect the leg assembly uponimp-act of the dolly with a surface must exceed the energy prestored insaid spring, and second cable means on the frame and on the leverelement for retaining the spring in preloaded condition, said legassembly, rst cable means, lever elements and said bar leverconstituting a multiplying linkage and cooperating with said spring toprovide a substantially constant deceleration suspension system for theframe.

2. A transfer dolly as recited in claim l, wherein the lever element ofsaid leg assembly is iconstituted by spaced parallel triangular platescarried by said -leg element with the leg element disposed therebetween,said leg assembly including additionally a brace extending between and 7secured to the plates at a point near the apices ofY said plates.

3. A transfer dolly yas recited in claim 1, including additionally acaster mount carried by the leg assembly at the lower end of the legelement, a yoke rotatable vin the mount, a caster carried by the yoke,and'means on the caster mount engageablerin said yoke for locking saidyoke against rotation in the mount.

4. A transfer dolly including a rectangular frame, guard rails on theframe, leg asemblies supporting said frame near each corner thereof,springs on the frame and connected to the leg assemblies, said legassemblies being deflectable against the tension of said springs uponimpact of the dolly with a surface therebeneatb, a sling for liftingsaid dolly, casters on the leg assemblies, brake mechanisms on thecasters, brake actuating means on the frame and connected with saidmechanisms, and means onthe sling and connected to said brake actuatingmeans and operable upon release of the sling for actuating the brakemechanisms for preventing movement of the dolly on such surfacefollowing said sling release.

' 5. A 'transfer dolly as recited in claim 4, wherein said brakemechanisms include brake cylinders and said brake actuating meanscomprises a master cylinder connected with said brake cylinders.

6. A transfer dolly as recited in claim 4, wherein said brake mechanismsinclude brake cylinders and said brake actuating means comprises amaster cylinder, a hydraulic line in fluid communication with the mastercylinder and brake cylinders, said master cylinder having main andauxiliary pistons, meansA connecting the sling to the auxiliary piston,and manually engageable means on the frame and connected to the mainpiston, said manually engageable means being operable for shifting the-auxiliary piston for releasing the brake mechanisms after actuationthereof by release of the sling.

7. A transfer dolly, as recited in claim 6, wherein said manuallyengageable means includes Va lever pivoted on one of the guard rails,and a connecting rod extending between one end of said leverand the mainpiston.

8. In a transfer dolly, a frame, a plurality of Wheel assembliespivotally mounted on the frame for supporting said frame above asurface, said assemblies being deflectable upon impact of the dollyYwith-such surface, each of said assemblies including a lever element, `aleg element connected to said lever element at an angle thereto, saidlever element comprising spaced parallel triangular plates having lowerend portions straddling the leg element at the point of pivotalconnection of the assembly with the frame, and a brace extending betweenthe leg element and points near the apices of the lever element, atorsion bar spring having one end secured to the frame and the other endaxially movable with respect to said frame, a bar lever on said otherend of said torsion bar, and a lcable connecting the bar -lever with thelever element, said torsion bar spring normally retaining the wheelassemblies in undeected position.

References Cited in the tile of this patent UNITED STATES PATENTS661,982 Harris Nov. 20, 1900 1,390,852 Woolley Sept. 13,1921 1,816,393Morris July 28, 1931 2,033,493 Straussler Mar. l0, 1936 2,305,807Gramatzki Dec. 22, 1942 2,395,768 Svoboda Feb. 26, 1946 2,512,941Johnson June 27, 1950 2,606,039 La Rue Aug. 5, 1952 2,730,375 ReimspiessIan. 10, 1956 2,792,231 Compton May 14, .1957 2,911,231 Allison Nov. 3,1959 FOREIGN PATENTS 995.581 France Aug. 22, 1951

